Anyone have success blocking Refugium light spill?

[PeterC99]

I get minimal light spill with this setup

 

[jassermd]

Similar setup here... had algae in my skimmer.
Picked up a sheet of black acrylic, cut it to size and used it to block the light. Works like a charm! No more algae in my skimmer.

 

[MMI]

I just hung up 2 pieces of black foam and that blocked out all the light from my skimmer and return pump.

 

[ILOVEYOUHALFISH]

Is that a kessil?